Having recently been writing about how the walls of old buildings appear to be performing better than we thought, it’s ironic to discover that recent research shows that some new homes appear to be falling well short of meeting their carbon emissions reduction targets. In some cases they’re exhibiting actual heat losses that can be more than double those predicted at the design stage.
The findings have been collated by the Good Homes Alliance (GHA) from research by Leeds Metropolitan University’s Centre for the Built Environment. Results from 15 heat loss tests, carried out by the University on a variety of new housing developments since 2005, have recorded losses of between 10% and 120% higher than designed. The average gap between designed and built performance was 60%.
Measurements of heating services also reveal that their performance was significantly lower than what was predicted at the design stage. In one field trial, undertaken for the Joseph Rowntree Foundation, the combined effect of high heat losses and an under performing communal ground source heat pump system resulted in carbon emissions some 140% higher than designed.
The GHA is working with its members to expand the evidence base. Meanwhile, these initial findings will do nothing to boost consumer confidence in new homes and raise further questions about how the housing sector is going to meet the necessary carbon reduction emission targets.
Image credit: Joseph Rowntree Foundation